Control mechanism



2 sheets-sheet 1 INVENTOR FQANK EQNY.y

ATTQRNEY BY y/ Sept. 8, 1942. F ERNY -ooNTRoL MECHANISM Filed. NOV. 16, 1940 sept. s, 1942.`

F. ERNYl CONTROL MECHANISM Filed Nov. v1e, 1940 2 Sheets-Sheet 2 l nwENToR` FQANK EQNY.

" ATTORNEY Patented Sept. 14942 .ulai'rrlli .s'rArEsQPAT-EN-T v-oli-Ql'cii-z 1- y CQNTBOLMECHANISM Frank Erny, KenmorerN. Y., assignor to Curtiss- Wright ware (Jorporation, a corporation of Dela- Appiicanos Ncvember-is, 1940, serial No. 365,959

Claims.

' This invention relates to aircraft and is concerned with improvements in control Vairfoil Ahinges and in operating means for control airfoils.

One of the objects lof the invention is to provide a `control. airf-oilhinge system which will maintain a minimum gap 'between the control airfoil and a xed wing or, airfoil as the control airfoil is movedto either side of a neutral plane.

Another object of the inventionis to provide foil 24 -is in'a neutral, fore and aft position. substantial continuations of the xed airfoil sur,- v

a simple and novel mechanism rior swinging the control airfoil about its hinge axes; anvassociated object is to coordinate the control vsystem with the hinge systemto secure a novel, simple andand movable airfoils showing the lhinge and conv trol system;

Fig. 2 is a sectional plan' on the line 22 of Fig. 1; f l

Fig. 3 is a section on the line 3-,3 of Fig. 1;

Fig. 4 is a section on the line 4-.4 of 3;

Fig. 5 is a section on the line 5-5 of Fig'. 1: and Y n f Y Fig. 6 is a diagrammatic front elevation of a control airfoil tapered inthickness'from its'root toward its tip, showing how the dual hinge axes according to the invention'may converge in sub-f stantial complement to `theconvergence of the airfoil surfaces across theairfoil span.

Referring first to Figs. 1j to 5, the general form of the hinge and controlwarrangement is shown as applied to a xed wing o) airfoil I0 having a thick trailing edge, the upperand lowersurfaces II and I2 of the wing being 4joined by a transverse bulkhead I3. Said upper and lower surarc of the track I8 is struck from a center 2| which is the intersection of the line I9 with the center line of the track` I1. The distance betweencenters 20 and 2I is indicated as d.

. A movable airfoil 24 comprises upper,-and lo'wer surfaces 25 and 26 which form, when the airfaces II and I2, the-front edges of said surfaces 25 and 26 lying closely adjacentthe rear edges of the surfaces II and 12. The airfoil 24 carries fore and'aft .bulkheads 21"one on each side of.

the hiding I6, these bulkheads supporting a cross bolt 28 on. which is journalled a roller 29 engag- -ing the track I1, and carrying a cross bolt 30 on which is journalled a'roller 3| engaging the track I8. The roller centers are spaced apart the diS- tance d. Itwill now 4be apparent that if the airfoil 24 isfrocked downwardly'from the neutral plane, as shown in Fl'g. 1,it will pivot about the center 20, -and the roller 29 will travel rearwardly in the arcuate trackl I1. If the airfoil is moved upwardly from the neutral plane' from the then current position, the'ro1ler 29 will travel back to concentricity with the center 2l, andthe airfoil will then rock about the center 2|, the

roller 3l travelling rearwardly in the track I8. Due to the convergence of the tracks I1- and I'8,

the movable airfoil 24 is constrained against bodily rearward displacement from the fixed airfoil I0, due to the fact that the center distance vfrom 20 to 2I is xed on both the control Aairfoil and on the xed airfoil.

It will be apparent that one skilled in the art could readily transpose the tracks I1 and I8 to the movableairfoil and the rollers 29 and 3l to the fixed eirpfoil, and likewise, the tracks n Vand I8 could be directed forwardly from the centers faces I I and I2 extend rearwardly of the bulkhead as at I4 and I5. To the bulkhead, a hinge fitting 1671s secured, this iitting in general comprising a fore and aft plate having two arcuate tracks I1 and I8 formed therein. The forward ends of said tracks terminate on a vertical line I9; the arc of the track I1 is struck from a center 26 which is the intersection of the vertical line I9 with the center line oi' the track I8. The

20 and 2i rather than rearwardly as shown.

Referring to the dotted view of the movable airfoil in Fig. l, it .will be apparent that the lower front edge of the surface 26 swings about the` center 28- and occupies'aposition within the connesof the trailing edge of the xed alrfoil, leaving a'. very small gap between the trailing edge of the lower xed airfoil-surface I2 and the lower surface of the movable airfoil. Also, the gap between the upper trailing edge of the xed airfoil and the upper leading edge of the movable airfoil will be .much less than would obtain if a single hinge were to be used between the two airfoils'.

'ro vswing the mcv'abie airfou 24 about its hinge system,-I provide a link or horn 34 pivoted to the airfoil 24 on a hinge 36 whose axis is substantially perpendicular to the chordal plane of the movable airfoil, whereby the link 34 must move about the hinge Il with the movable airfoil but.

may move laterally or spanwise with respect to the airfoil. 'I'he link passes through an opening in the wall I3, and the front end 4of the link L is formed with a ball end Il, embraced by a assuma 4 2. In an airfoil system, a fixed wing having a recessed trailing edge defining at its border a tion of the pulley 38 carries with itthe ball end i It, forcing the link 34 and the airfoil 24 tc move up or down about the airfoil hinge, during which movement the link 36 may swing freely in a spanwise direction about its hinge 35.

Reference may now be made to Fig. 6 which shows diagrammatically the airfoil 24 in front view, the zone A being the region in which the elements of Figs. 1 to 5 are disposed. The airfoil 24 is shown as being tapered in thickness from left to right and to coordinate the double hinge axis arrangement of the invention with vthis taper, the hinge axes and 2| may lie substantially parallel with and close to the lower and upper surfaces of the airfoil, whereby the hinge axes 20 and 2| converge from a wide spacing at zone B to an intersection at zone C. If a plurality of hinge ilttings are to be used throughout the airfoil span, such as at zones A, B, and C, the tracks VII and I8 at zone B are spaced wider apartand are struck on arcs equivalentto the spacing between the axes 20 and 2| at the zone. At zone A, the system is as shown in the other figures while at zone C no tracks Y are necessary but a'single hinge system of conventional pattern may be utilized. It is contemplated that only a single form or link such as 34 need be used for the whole control airfoil.

While I have described my invention in detail in its present preferred embodiment, it will be obvious to those skilled in the art, after understanding my invention, that various changes and modifications may be made therein without departing from the spirit or scope thereof. I aim in the appended claims to cover all such modiilcations and changes.

I claim as my invention:

1. In an airfoil system tapered spanwise in thickness, a fixed airfoil having a substantially flat trailing edge normal to the airfoil chord plane, hinge means defining two hinge axes one close to one side of the airfoil trailing edge and one close to the other side of the airfoil trailing edge, said hinge axes converging toward one an`- other, spanwise, in accordance with the taper of the airfoil system, a spanwise tapered control airfoil having devices engaging said hinge means, mechanism to move the airfoil upon said hinge 'means and reliefs at said hinge means to allow of control airfoil movement to one side of neutral about the hinge axis closest to the one side, and to allowof control airfoil movement to the other side of neutral about the other hinge axis closest to the other side.

polygon normal to the wing chord plane, a movable control airfoil having a substantially ilat similarly polygonal leading edge normal to the airfoil chord plane. said edges lying adjacent one another, a series of alined fulcrums along each border of the trailing edge,.means along the borders of the leading edge engaging said fulcrums. and means to swing the control airfoil to one side of neutral on one series of fulcrums and to the other side of neutral on the other series of fulcrums, portions of the leading edge, during such swinging, entering int the recessed trailing edge of the fixed wing.

3. In an airfoil system, a fixed wing having a recessed trailing edge defining at its border a polygon normal to the wing chord plane, a movable control airfoil having a substantially flat similarly polygonal leading edge normal to the airfoil chord plane, said edges lying adjacent one another, a series of alined fulcrums alon'g each border of the trailing edge, means along, the borders of the leading edge engaging said fulcrums, and means to swing the control airfoil to one side of neutral on one series of fulcrums and to-the other side of neutral on the other series of fulcrums, portions of the leading edge, during such swinging, entering into the vrecessed fulcrum series tapering toward one another and l said wing and airfoil tapering in the thickness throughout their spans in corresponding degree. 4. In aircraft, a fixed forwardy airfoil, a movable rearward airfoil, the forward part of the movable airfoil lying adjacent to the rearward edge of the xed airfoil. a hinge unit between said airfoils including two hinge pins on the movable airfoil, one pin lying l.adjacent the airfoil top surface and the other lying adjacent the airfoil bottom surface, said hinge unit including a fitting on the ilxed airfoil having arcuate slots within which said pins engage, whereby upon down airfoil movement the lower pin comprises the hinge pin and upon up airfoil movement the upper pin comprises the hinge pin, the hinge pins being disposed in the airfoil so that .the upper and lower surfaces of the iixed and movable airfoils have substantially no gap therebetween and substantially no foreshortening of airfoil effective chord length as the movable airfoii is moved, respectively, up' and down.

5. A movable-airfoil-to-xed-airfoil.hinge Joint wherein the airfoils at the joint have substantial thickness comprising separate hinge pins locatedone adjacent to one `surface of and the other adjacent to the opposite surface of onel said airfoil, means carried by the other said airfoil with which said hinge pins are adapted to cooperate, said movable airfoil being movable in one direction about one said hinge pin to maintain minimum gap at one side of said hinge joint and being movable in the lopposite direction about the other said hinge pin to maintain minimum gap at the opposite side of said hinge joint, and means operable to so move said movable airfoil.

FRANK ERNY. 

